The temporary styling of hair for a prolonged period of up to several days usually requires the use of active setting agents. Hair treatment means which are used for the temporary shaping of hair therefore play an important part. Corresponding means for temporary reshaping customarily contain synthetic polymers and/or waxes as the active setting agent. Means for assisting the temporary reshaping of keratin-containing fibres may be manufactured in the form of hairspray, hair wax, hair gel, hair mousse, for example.
The most important property of a means for the temporary reshaping of hair, hereinafter also referred to as a styling agent, is that of giving the treated fibres the strongest possible hold in the newly fashioned style—i.e. a style impressed on the hair. This is also referred to as a firm hairstyle hold or the strong hold of the styling agent. The hold of the hairstyle is substantially determined by the nature and quantity of the active setting agents used, wherein, however, the further constituents of the styling agent may also have an influence.
Apart from a high degree of hold, styling agents must meet a whole host of other requirements. These can be roughly divided into properties on the hair, properties of the respective formulation, e.g. properties of the mousse, gel or sprayed aerosol, and properties that relate to the handling of the styling agent, wherein particular importance is attached to the properties on the hair. Particular mention should be made of moisture resistance, low tack and a balanced conditioning effect. Furthermore, a styling agent should be universally applicable to all hair types and be kind to hair and skin.
In order to satisfy the different requirements, a plurality of synthetic polymers has already been developed as active setting agents, which synthetic polymers are used in styling agents. The polymers can be divided into cationic, anionic, non-anionic and amphoteric setting polymers. Ideally, when applied to hair, the polymers produce a polymer film which, on the one hand, gives the hairstyle a strong hold but, on the other hand, is sufficiently flexible not to break when subject to stress. If the polymer film is too fragile, so-called film flakes, in other words residues, are formed which become detached when the hair moves and give the impression that the user of the styling agent concerned has dandruff. Similar problems result when waxes are used in the styling agent as the active setting agent. If the styling agent is a gel or a paste, the polymers should also have thickening properties.
Anionic polymers known in the art which are used in hair-setting products are crosslinked anionic amphiphilic polymers which contain a (meth)acrylic acid unit and a (meth)acrylic acid oxyalkylene alkyl ester unit. Polymers of this kind are described in European patent EP 897 711 B1 and German patent applications DE 102011077364 A1 and DE 102009001978 A1, for example, and are commercially available, e.g. by the name Aculyn®88 (INCI: Acylates/Steareth-20 Methacrylate Crosspolymer). DE 10 2011 077 364 A1 and DE 10 2009 001 978 A1 relate to the use of a polymer of this kind, in particular also Aculyn® 88, in combination with a further special crosslinked anionic polymer for the temporary reforming of hair.
A structurally similar polymer is commercially available by the name BALANCE® RTF (INCI: Acrylates/Ceteareth-20 Methacrylate Crosspolymer), wherein the function thereof in styling products is substantially that of a thickening agent and film former.
Furthermore, hydrophobically modified acrylate copolymers (INCI: Acrylates Copolymer (and) Water) are commercially available which essentially act as a thickening agent. The AquaStyle® SH-100 Polymer (Ashland Inc.) data sheet describes an acrylate copolymer of this kind and the use thereof in combination with carbomers. Suitability for crystal-clear hair gels, good initial stiffness, moisture resistance and high-humidity curl retention are described.